1. Field of the Invention
The present invention relates to NAND memory cells, and more particularly, to NAND memory cells having islanding gate structures and manufacturing method thereof.
2. Description of the Prior Art
Non-volatile memory devices have been commercially used nowadays. The non-volatile memory device comprises mask read-only memory (Mask ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), and Flash Memory. A NAND flash memory device is a common type of the flash memory device.
With a trend toward miniaturization of the semiconductor industry, it is getting more and more difficult yet critical to precisely control the line width of the word lines and the line space between each two adjacent word lines of a NAND memory cell array.